Antibiotic overuse targeted since it can cause drugs to be ineffective

Published: November 27, 2011 8:00AM

In our pill-seeking society, a medical visit hardly seems complete if we aren't "given something" for what ails us.

Much of the time, the prescription is for an antibiotic -- drugs that have saved millions of lives from infection for more than 70 years, but that have also been widely overused to the benefit of some nasty germs.

Widespread antibiotic use in people and farm animals and their resulting spread into the environment is a major public health concern because it contributes to the spread of antibiotic resistant strains of bacteria.

"The threat of untreatable infections is real," said Dr. Arjun Srinivasan, who heads up health education programming for the federal Centers for Disease Control and Prevention.

"Although previously unthinkable, the day when antibiotics don't work in all situations is upon us. We are already seeing germs that are stronger than any antibiotics that we have to treat them."

The CDC estimates that $1.1 billion is spent each year on unnecessary or useless antibiotic prescriptions for adult upper respiratory infections alone.

Although efforts encouraging doctors to be more careful with prescribing -- and patients more cautious about asking for antibiotics -- have reduced overall antibiotic dispensing, a new report by the "Extending the Cure" program at Washington's Center for Disease Dynamics, Economics and Policy shows the trend is not consistent around the country.

Based on surveillance done at a national network of labs that tracks drug-resistant microbes, between 1999 and 2007, the latest year data is available, antibiotic consumption fell 12 percent.

But the tracking also showed that a cluster of Southeastern states -- including West Virginia, Kentucky, Tennessee, Arkansas, Alabama and Louisiana -- had antibiotic use rates twice as high as states along the Pacific Coast and the Southwest.

Nationally, the prescription rate for all classes of antibiotic was 858 per 1,000 people, or 0.86 per person. But in Alaska, there were just over 545 scripts written per 1,000, or 0.55 per person, while in West Virginia, there were 1,221 prescriptions, or 1.22 dispensed for each person in the state.

The researchers published a report on a new Drug Resistance Index that can track changes in the effectiveness of a particular antibiotic over time.

For instance, prescription rates for the broadly effective class of antibiotics called fluoroquinolones went up by 49 percent between 1999 and 2007, yet those drugs are now seven times less likely to work against all strains of E. coli than they were just eight years ago.

Oddly enough, even though heavy antibiotic use is at least as common in hospitals as physician offices, the CDC has mainly tracked use through physician offices and other outpatient settings.

The agency just announced it was setting up a separate electronic surveillance system on use of the drugs in 4,800 hospitals that are part of a health care safety network. The hospitals will be able to monitor what they're using and compare their use to other hospitals, as well as contribute to regional and national data.

Not all drug-resistant bugs develop or are spread solely among people. One recent study of treated wastewater in Ann Arbor, Mich., found high levels of at least one superbug, Acinetiobacter, near discharge points, although levels diminished downstream fairly quickly.

Researchers from the University of Michigan say treatment plants offer perfect conditions for bacteria to boost their resistance in the presence of drugs that have either been directly flushed into the system or that have been carried along through human waste.

Concern has also been focused on widespread use of antibiotics in farm animals, poultry and even fish as preventive measures or to promote growth. The practice breeds resistance largely because as much as 90 percent of the drugs are released as waste, but also because animal stomachs act as petri dishes for superbugs.

Although the Food and Drug Administration recently turned down a petition from food safety groups to ban non-therapeutic use of antibiotics in farming, the European Union has endorsed ending the practice.

FDA officials said they would work with industry to reduce antibiotic use, and there are already a number of experiments with changing animal diets or even alternative supplements in place of the drugs.

One project funded by the USDA's Agricultural Research Service has been feeding cattle in Texas orange peels and pulp to reduce levels of pathogens such as salmonella and E coli in each animal's gut. The researchers also have done studies in sheep.

For more information on antibiotic resistance, turn to these websites: